Tears streamed down her face as she quietly eyed a memorial for her son, 17-year-old Darnell Williams, who was shot to death a few days earlier. Teddy bears half-buried in snow held signs that read "We love you, 'Lil Nelly.' R.I.P."

The teen had left his house in the first block of East 102nd Place just before 3 p.m. Thursday. He was going to pay his cellphone bill, his mom said.

Moments later, shots rang out.

"I ran to the window and saw him lying on the ground," said Tanika Williams, 33.

She ran outside and held her son, who had been shot multiple times and was gasping for breath. His eyes rolled back as they waited for paramedics.

"In the back of my mind, I kind of knew, but I didn't want to believe it," Tanika Williams said. "I'm not supposed to be burying him. He's supposed to be burying me. ... Who wants to bury their child?"

Police said two armed men had approached him and opened fire about 2:50 p.m. A motive wasn't clear, and no one was in custody as of Tuesday. Neighbors and relatives think the shooting was a case of mistaken identity.

Darnell Williams had survived a separate shooting in June, police said. He "got into it" with some guys at the community pool, according to relatives, and one of them shot him in his leg.

Cops didn't know whether the June and December shootings were connected. Relatives said they know who shot Darnell Williams in June, but are in the dark about the shooting that claimed his life.

"Clearly this stuff happens on the regular [basis]," Tanika Williams said. "You know how people say, 'My son was a good kid?' My son was a good kid. ... He helped out older neighbors. He wasn't in the streets."

By midday Tuesday, about a dozen relatives had gathered in the Williams living room to help make funeral arrangements. Near the front window stood a Christmas tree adorned in sparkly reds and whites. Outside, strips of leftover red police tape were barely distinguishable from holiday decorations.

Darnell Williams "was silly," his mom said with a smile. "He'd come into a room and would do something silly to brighten it up. Or just say something silly."

Tanika Williams called her son her "little man." He was handy around the house and loved working on cars. He hoped to own his own car wash and auto repair shop one day.

"All his life, he would see a car and be like, 'I'm going to get me one of those,'" said Tanika Williams, whose relatives taught her son about car repair.

Darnell Williams wasn't in school, his family said. Instead, he worked for the Woodlawn Community Development Corporation, Heavenly Angels Funeral Services and as a car washer.

The teen was close to his four sisters and two brothers, relatives said. He liked staying home and watching movies and had always been quite the ladies' man.

"He'd be so funny. Even my friends, he'd flirt with them," his mom said with a laugh. "I was always telling him, [these girls] are going to team up on you and kick your butt. They're going to come over here at the same time and kick your butt."

Tanika Williams said she hopes her son's killers are caught so "justice can be served."

"Some of these young guys have no value for life," she said. "To take somebody else's life — you've got no heart, no conscience. How can you sleep knowing you just killed somebody? How can you sleep at night? How can you still romp around?"

My son "should've had longer. I had 17 long, beautiful years that I'll never forget," Tanika Williams continued, fighting tears. "I wish I could have 17 more. And 17 more. And 17 more."